2" of water left in bottom after cycle

I could not have accomplished this repair without this site. It lead me not only to the problem but what parts would be needed. Since the pump worked okay I decided the water must be draining back from the hose since the bottom of the washer was lower than the discharge point of the drain hose. I thought there must be a check valve someplace. When I found PartSelect it was easy to go to the brand of dishwasher, model number, symptom and lots of advice from people with the same repair in the past. I decided to go with the piston and nut assemble (check valve) and the valve flapper. On the web site there was a blowup diagram that showed where the part was and advice on how to properly install the parts. When I looked at the old check valve and the new one you could easily see that was the problem. Replacing the flapper was added insurance.